Research On Reliability Improvement Of Flip Chip LED

Light Emitting Diode(LED)is widely used in display and lighting with its advantages of energy-saving,environment protection.There are three common structures:lateral chip,flip chip,vertical chip.Flip chip has a better performance than the traditional lateral chip,and compare with the vertical chip,flip chip has relatively simple and high yield production process.Compare with Wire bond used in lateral chip and vertical chip,flip chip is facing with the problem of reliability due to die bond package,because die bond has bigger bond size than wire bond.Base on the flip chip product of enraytek,a lot of analysis were done,we found that most of the failure come from the sidewall or the front of chip;The failure of flip chip has been depleted with the isolation of different chip,the protection of the sidewall,material replace,and special design for escaping the damage of pin when chip grabbing.For the research on reliability improvement of flip chip product,the following works were done:(1)The analysis was showed to make sure that the model of failure come from P pad sidewall and middle of Chip.(2)Different DOE was set up to conform the effect and feasibility,include Isolation and special design test.(3)The test data was summarized and DOE plan was optimized,metal profile change for N pad sidewall failure improvement(4)The chip's reliability was tested and the reliability data was showed.(5)To be further discussed problems were pointed out,and the development proposal were forward,just like dielectric layer and metal layer profile improvement.